The Military Complex at the penal colony of Port Arthur, Tasmania, is situated in a prominent position overlooking the harbour. It is the third
military complex on the site and was built in 1847, with the central tower built in 1836. Both were built during the rule of Commandant Charles O’Hara Booth (1800-1851) and they are situated next to the Commandant’s House which was built for him. The complex was built with convict labour, and the stones of the central tower were shaped by the boys at the nearby Point Puer Juvenile Establishment. No doubt in part due to practical considerations, the Military Complex resembles a medieval castle, with the central round Guard Tower flanked by two smaller round towers, all of which are topped by crenelated parapets. The towers are separated by a strong stone wall.
For the Guard Tower see http://ausmed.arts.uwa.edu.au/items/show/1139
For a smaller round tower see http://ausmed.arts.uwa.edu.au/items/show/1144